GB patent No.1 320 481 discloses certain gem-diarylethylene derivatives having anti-histamine activity.
Effective antipsychotic (neuroleptic) agents include tricyclic phenothiazines, thioxanthenes and dibenzazepines as well as benzamides and butyrophenones. These compounds block dopamine D2 receptors and inactivate dopamine transmission. As a result of this, these compounds induce characteristic neurological side effects in man such as extrapyramidal side effects e.g. dystonia and dyskinesia (R. J. Baldessarini, 1996, Goodman and Gilman's The Pharmacological Basis of Therapeutics 9th ed., eds J. G. Hardman et. al.). In animal tests such side effects manifest themselves as catalepsy. It would be advantageous therefore to provide a series of antipsychotic agents which do not have these debilitating side effects.